MINNEAPOLIS (AP) - The coldest temperatures of the season delayed the start of school for many students and caused even the hardiest Minnesotans to think twice about staying outdoors for any length of time.

The National Weather Service issued an "extreme cold warning" for northern Minnesota through midmorning Friday. Temperatures, even without the wind chill factor, dropped to below zero double digits. International Falls and Babbitt had readings of 46 below.

The Duluth News Tribune reports the 46-below reading was a record low for International Falls. The city's previous record for Jan. 21 was 41 below set in 1954.

A wind chill advisory was in effect for much of the rest of the state. Minneapolis Public Schools advised parents that keeping their children at home Friday would count as an excused absence.

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